Insurance companies are far from stupid.These are financial institutions we're talking about here.They rely on a reasonable sector of the market being lazy and ignorant and they'll get away with whatever we allow them.I remember my very first large CC insurance application (Suzuki RF600r).I read an article in Which Motorcycle Magazine that advised readers to ring around 6-10 companies getting the lowest quote then ring absolutely any one of them back removing between 15 and 20% from the lowest quote and you'll get a result.
My initial quotes for that bike were between £600-£700 and eventually settled on £169.That was 3rd party 20 years ago
Two years ago I was paying £120 fully comp then after an accident in 2012 incurring over £2000 worth of damage to the bike my premiums went up by £20,my renewal has just come in and it's back down to £120 fully comp with low excess and all the whistles and bells.
I always use a High Street broker now and within reason you can more or less tell them what you want to pay